Grundig GUVLDHD3200

[tom66]

Re: Grundig GUVLDHD3200

Unfortunately, the TV died a few days later with a black screen, and the same fet shorted. It's nigh impossible to source a T-con for me, so I'm selling it for parts on eBay in the hope someone else can. But it seems that something goes wrong on these boards that kills the new FET quickly. I'm not sure what it is.

[vinceroger69]

Re: Grundig GUVLDHD3200

thats a shame but hopefully you will get your money back on it.

[momaka]

Re: Grundig GUVLDHD3200

If you feel experimental, perhaps try a bigger MOSFET then? Or parallel 2 or even 3?

[tom66]

Re: Grundig GUVLDHD3200

If you feel experimental, perhaps try a bigger MOSFET then? Or parallel 2 or even 3?

It was hard enough getting one to fit. I've decided it will be a parts TV.

[vinceroger69]

Re: Grundig GUVLDHD3200

its always worth having parts tvs imo the lcd screen alone is always worth keeping my pile of circuit boards is building up lol. also this is one of your own posts tom66 whats your opinion on picture quality on rear projection sets i have been offered 2 lately one with a cracked front perpex screen? one working very cheap are these any good picture wise i have never seen a working one myself.I understand led/lcd are better but being as these rear projection sets are cheap are they called for if i wanted to sell them on?.

[tom66]

Re: Grundig GUVLDHD3200

its always worth having parts tvs imo the lcd screen alone is always worth keeping my pile of circuit boards is building up lol. also this is one of your own posts tom66 whats your opinion on picture quality on rear projection sets i have been offered 2 lately one with a cracked front perpex screen? one working very cheap are these any good picture wise i have never seen a working one myself.I understand led/lcd are better but being as these rear projection sets are cheap are they called for if i wanted to sell them on?.

My pile is taking up the garage...

Regarding rear projection, under 60" I wouldn't bother, parts are near impossible and not worth much anyway.

[vinceroger69]

Re: Grundig GUVLDHD3200

cheers wont bother with them in that case my pile of bits was taking up a whole spare room in our old flat mainy crt tvs and bits no lcd new house shed filling nicely lcd tv monitors pity 3/4 of them are for parts lol if i see one with a smashed screen etc i still pick it up as good for boards /parts just ned some with good screens to fix out of the bits pile. on a different note hows the other 2 sets you was repairing?

[tom66]

Re: Grundig GUVLDHD3200

cheers wont bother with them in that case my pile of bits was taking up a whole spare room in our old flat mainy crt tvs and bits no lcd new house shed filling nicely lcd tv monitors pity 3/4 of them are for parts lol if i see one with a smashed screen etc i still pick it up as good for boards /parts just ned some with good screens to fix out of the bits pile. on a different note hows the other 2 sets you was repairing?

I've got exams but the 42" should be fixed next week then I'll take a closer look at the Pioneer - may just disable the protection and see if anything goes bang.

[vinceroger69]

Re: Grundig GUVLDHD3200

cool good luck with the exams.

[tom66]

Re: Grundig GUVLDHD3200

Well, I looked again at my shopping cart and found I'd ordered a 2.7A MOSFET - at the time, I thought this would be more than sufficient.

However looking closely at more and more T-con app notes it seems that the main Vs rail actually uses about 1 amp at 15V, so a 2.7A FET would be breaking the limit (3A @ 5V in), especially when switching losses are accounted for and the high internal temperature these TVs reach (including the T-con with little/no airflow in its shield.)

I'm going to source a 10A SOT23 FET and give it another go if it is possible to fix again, given the nightmare it was originally.

[momaka]

Re: Grundig GUVLDHD3200

Let us know how it goes. Also, how did your exams go?

[dj12dj1]

Re: Grundig GUVLDHD3200

Could you take a look at my Grundig GUVLDHD3200... it's suffering from the same problem! I think you're Yorkshire based like myself but understand if you'd rather not. regards - Dave